This chapter is from the book

This chapter is from the book

The competitive business climate demands increasing data storage capabilities ranging from availability and recovery, to capacity
management, to vendor aggregation. Multiprotocol storage networks serve all of these requirements in the form of block-based
SANs or file-based NAS. As an enabling platform, networked storage naturally assumes a greater role in the cost and control of the overall storage
infrastructure. Chapter 4, “Storage System Control Points,” covered the control aspects of the storage fabric, outlining the areas of intelligence for storage services and the importance
of balancing the fabric layer with the host and subsystems layer. This chapter covers the cost component of the storage networking
layer by looking at the strategic reasons to combine both defensive and offensive measures and the value achieved by doing
so across a common networking platform.

The Internet took the world by storm. The mad dash to put anything and everything digital onto a single network, whether for
educational, government, commercial, or experimental reasons, led to data storage requirements and capacity not previously
anticipated. Today, many commercial elements of the Internet have reworked business models and adjusted storage capacity requirements.
Have you noticed all of the storage capacity restrictions on “free” Web site services, such as online photo sharing and Web-email
boxes? Have you noticed how many times you are offered a chance to “upgrade” to the monthly fee option with more storage?
Managing storage on the Internet, or for that matter, on any networked environment, includes capital and operational costs
that hit the bottom line.

In industries where storage availability and protection drive revenue-generating businesses, the networked storage budget
grows as a function of the overall operating budget. To harness these costs and drive ongoing returns from the investment,
companies must broaden the metrics for measuring returns. This comes through merging defensive strategies like data protection
with offensive strategies like platform consolidation.

5.1 Balancing Offensive and Defensive Strategies

The race to digitized information, which requires 100 percent uptime guarantees, coupled with the world political climate,
has driven the role of defensive storage strategies in almost every medium to large corporation. Data storage availability
and protection have become the hot topics of the last five years, serving to keep applications up and running, and to restore
capabilities at hand if needed in the event of a site disaster. From a budgetary process, these requirements often fly through
approval processes compared to other requests. Few executives are willing to tolerate the costs associated with downtime for
e-commerce-related business or the costs of losing critical business information that cannot be recovered.

Given this preoccupation with data protection, the build-outs in many organizations have focused on these defensive approaches.
Networked storage environments, as the very backbone of data availability and protection mechanisms, are often categorized
under this umbrella. In many cases, this provides for adequate project justification. But companies that consider only a defensive
approach to storage networking cannot reap the full benefits provided by this infrastructure.

Offensive strategies for storage networking fit hand in hand with defensive strategies but also further maximize the value
of a networked storage environment. By looking beyond traditional concepts of data protection to entirely new methods for
handling storage, offensive strategies help companies “change the game” and uncover opportunities for operational agility
and flexibility that directly impact both capital and operational costs. The primary advantage of a dual-pronged approach
to SAN deployment is that the underlying principals of the networked storage environment are similar across both strategies. For
example, the same SAN plumbing used to facilitate more efficient backup operations also fits effectively within the larger context of corporate
networking, particularly with the flexibility of IP SANs.

Offensive and defensive strategies often overlap. Depending on individual corporate planning processes, the lines between
offensive and defensive approaches may vary. Even with a potential gray zone between strategies, the model helps IT professionals evaluate options beyond those traditionally considered for SANs. Figure 5-1 outlines some general distinctions between offensive and defensive strategies.

With defensive strategies, cost savings frequently relate to short-term objectives, typically the greatest pain points in
the process. For example, a company unable to complete regular backups due to excessively long backup windows may adopt a
SAN to alleviate the problem. In the race to solve such pressing issues, other considerations may be left out of the picture.
For example, will the backup solution also help with storage consolidation? Is it replicable at other offices and locations?
Does it fit with requirements for offsite storage in addition to simply reducing the backup window? These questions generally
fall into medium- and long-term savings categories associated with offensive strategies.

Asset focus also differs between approaches. The defensive approach focuses on maximizing the use of existing assets, such
as extending the life of a tape library by sharing it across multiple servers or using storage resource management to help
grab additional capacity from inefficiently used RAID devices. The offensive approach looks at both current and future assets, such as what devices are likely to be part of the
infrastructure over time, how they will be managed, and what the best options are for building an infrastructure to accommodate
them. For example, balancing a combination of current block-accessed SAN devices with new file-accessed NAS devices requires a platform consolidation approach that is best achieved with a common networking infrastructure such as
Ethernet and IP.

Platform choice differs between offensive and defensive approaches. Defensive strategies lean towards conventional platforms,
taking incremental moves towards SAN deployment. The typical scenario is a company that has several Fibre Channel servers with DAS devices that moves towards a Fibre Channel SAN. While this deployment will provide SAN benefits, such as higher availability and more efficient backup operations, it still leaves gaps for solutions such as remote
backups and integration with NAS. An offensive approach would be to move towards an IP storage network. This leapfrog step provides all the benefits of a
SAN, but also gives the ability to keep all the Fibre Channel servers and storage devices with a SAN primarily based on IP networking. While IP as a SAN platform may fall in to the “emerging” category in the storage world, IP and Ethernet have longstanding maturity and robustness
from decades of use in the networking world.

5.1.1 Risk and Total Cost of Ownership

Along the lines of comparing deployment approaches, another view of offensive and defensive strategies looks at overall storage
growth affecting risk and total cost of ownership (TCO). The proliferation of data storage capacity coupled with the corporate requirements to maintain effective storage management
increases both risk and TCO. From a risk perspective, the increase in the amount of data translates into exposure to potential loss. For example, companies
relying on customer databases to deliver products and services face potential revenue loss if that information is lost or
becomes unavailable. The primary concern for that operation is data protection and availability to reduce the amount of risk.

Increases in the total amount of storage also drive up the TCO. TCO typically includes the capital equipment acquisition costs plus the operational costs over a fixed time period. Companies
that try to maintain traditional storage architectures, such as DAS, in the face of ballooning capacity requirements quickly find themselves in a never-ending race to add more storage to more
servers while watching management and administration costs skyrocket. In this case, storage network deployment facilitates
more rapid expansion of new storage capacity without directly impacting individual server or application operation. With the
flexibility of a networked infrastructure in place, total costs decline.

Figure 5-2 shows the effects of storage growth on risk and TCO. In both cases, storage networking strategies—offensive and defensive—help corporations mitigate these effects.

The clear distinction between the approaches is used primarily as a thought framework for the chapter. Certainly, there are
defensive approaches that reduce TCO and offensive approaches that reduce risk. However, by separating these two driving forces, IT professionals can more effectively position the project justification and return on the investment when considering storage
networking deployment.